1. Technical Field
The present invention relates to a head mounted display.
2. Related Art
A head mounted display (HMD) which is a display mounted on the head is known. The head mounted display generates image light representing an image by using, for example, a liquid crystal display and a light source, and guides the generated image light to user's eyes by using a projection optical system or a light guide plate, thereby allowing the user to recognize a virtual image. The head mounted display includes a wired interface such as a universal serial bus (USB) or a wireless interface such as a wireless LAN, and thus can be connected to an external apparatus such as a portable information terminal (for example, a smart phone or a tablet).
JP-A-2013-92781 discloses a configuration in which a display destination is determined depending on open and close states of a portable information terminal when a predetermined function mounted in the portable information terminal is displayed on either a display screen of the portable information terminal or a display screen of a head mounted display. JP-A-2012-44429 discloses a configuration in which a head mounted display displays partial image which is at least a partial region of an image which is currently displayed on a portable information terminal. JP-A-2013-93705 discloses a configuration in which a head mounted display displays a part of an image indicated by image data received from an information terminal on the basis of head posture information of a user.
In the technique disclosed in JP-A-2013-92781, there is a problem in that there is no sufficient study of a method of displaying a predetermined function mounted in the portable information terminal on a display screen of the head mounted display. In addition, in the technique disclosed in JP-A-2012-44429, there is a problem in that, since a partial image of the portable information terminal is displayed on the head mounted display without change, a front side of the eyes of a user is blocked by the partial image, and thus the user may feel uncomfortable. Similarly, in the technique disclosed in JP-A-2013-93705, there is a problem in that, since a part of an image indicated by image data from the information terminal is displayed on the head mounted display without change, a front side of the eye of a user is impeded by the image, and thus the user may feel uncomfortable.
For this reason, it is desirable to display a display screen of an external apparatus on the head mounted display by using a display mode of an image which is suitable for the head mounted display. In addition, in the head mounted display, there are various demands for improvement of usability, improvement of versatility, improvement of convenience, improvement of reliability, and manufacturing cost reduction.